One such container is described in French patent specification No. 80-21565.
Such a container is effectively proof against external splashes of liquid which may occur after it has been filled.
Further, the cover is easily lifted off the container even though it does not include a handle which could cause difficulty when cleaning.
It has been observed that to ensure good conservation of food in the container, it is necessary either to have very slight ventilation or else considerably greater ventilation depending on the nature of the food.
Thus, fresh or cooked vegetables require slight ventilation whereas raw meat requires greater ventilation.